A cosmetic composition for keratin fibers such as hair, for example, a hair coloring composition and a hair permanent waving composition, includes an alkaline agent. Very often alkaline agents have an offensive odor.
As the alkaline agent, ammonia is commonly used.
Ammonia is an excellent alkaline agent in terms of safety and performance of cosmetic treatments for keratin fibers. However, its malodor gives a strong negative influence to the usage of a cosmetic composition including ammonia for keratin fibers. Therefore, elimination of ammonia odor from the cosmetic composition is one of the important targets nowadays in the field of cosmetics for keratin fibers.
The current main method for reducing ammonia odor from a cosmetic composition for keratin fibers (this means evaporation of ammonia (odor) from the surface of the cosmetic composition) is to use another alkaline agent such as monoethanolamine instead of ammonia or to replace a part of the ammonia as disclosed in JP-A-H01-213220 (1989). However, monoethanolamine has an amine odor and this method also unfavorably affects the performance of cosmetic treatments for keratin fibers. For example, the ability to lift hair or intensively color hair, both of which are very important factors for coloring hair, is negatively affected when coloring hair using a cosmetic composition including an alkaline agent other than ammonia. In addition, the use of an alkaline agent other than ammonia sometimes causes a change in hair color, apart from the target color, which imparts a negative impact on the formula design of a cosmetic composition for coloring hair.
Accordingly, the above method is not appropriate when cosmetic performance for keratin fibers should have priority.